Tapered boring attachment



Nov. 18, 1947. v. MEADOR ETAL TAPERED BORING ATTACHMENT 4 Sheets-Sheet 1 Filed May 2, 1.945

In INVENTORS I x. .Z:.%Ma 207" Nov. 18, 1947. v. MEADOR' EI'AL' I I 2,431,269

TAPERED BORING ATTACHMENT INVENTORS Z.%Meaior fie RJMfianz'eZ v. MEADOR ET AL 2,431,269.

TAPERED BORING ATTACHMENT Filed May 2, 1945 4 Sheets-Sheet 5 LZMediar JNVENTORS NOV. 18, 1947. VTMEADOR ETAL 2,431,269

TAPERED BORING ATTACHMENT Fil ed May 2, 1945 4 Sheets-Sheet 4 INVENTORS iLKMeador v ficfjlfcfianz'e Z Patented Nov. 18, 1947 TAPERED BORING ATTACHMENT 1 Louis v. Meador and Roy J.' McDaniel, 1 j

Vinto'n, Va.

Application May 2-, 1945, Serial No:'.'591, 538.

s Claims. (urn-st] This invention relates to tapered bores.

An object of this invention is to provide a tool in the form of an attachment for a boring machine either vertical or horizontal, which will make it possible to'bore tapered holes with any selected taper.

Another object of this invention is to provide a device of this kind whichcan be very finely adjusted so as to form a precision cut opening and eliminate the necessity of subsequent reaming or other smoothing operation.

A further object of this invention is to provide an attachment of this kind which includes a frame or cage for attachment to the rotating face plate of the boring mill, the cage including adjustable guide means which is engageable by a tool holder so that as the tool holder is moved lengthwise through the rotating cage the tool holder will travel on an angle to the line of travel of the spindle.

A further object of this invention is to provide an eccentric adjusting ring for the tool holder guides which is adjustably carried by the cage so that the degree of tapercan be finely regulated, and if desired the tool holder can be adjusted to out only a straight hole.

A further object of this invention is to provide a tapered bore attachment of this kind which is simple in construction so that it can be sturdily made and will provide for the accurate cutting of the desired size of bore which may be either straight or tapered and will permit the boring of the hole from either end.

To the foregoing objects .and others which may hereinafter more fully appear, the invention consists of the novel construction, combination and arrangement of parts as will be more specifically referred to and illustrated in the accompanying drawings, but it is to be understood that changes, variations and modifications may be resorted to which fall within the scope of the invention as claimed. y

In the drawings:

Figure 1 is a longitudinal section partly broken away of a tapered boring attachment constructed according to an embodiment of this invention,

' Figure 2 is -asectional View taken on the line 2-2 of Figure 1,

Figure 3 is a sectional 33 of Figure 1,. i

Figure 4 is anexploded'side elevation partly broken away of the device,

Figure 5 is a fragmentary end elevation of the inner cage member showing the cage plate,

view taken on the line boring tools for boring 2 Figure'dis a sectional View taken on the line UlQl tj,

Figure 7 is a fragmentaryrear elevation of the device, 1

Figure 8 isa fragmentarysectional view showing one of the tool holder bar mountings, and Figure 9 is a sectional. View taken on the line 99 of Figure 2. Q Referring to. the drawingsthe numeral ll) designates generally a face plate which is secured to a rotatable boring mill construction and has movableendwise therethroug h aspindle II; The spindle II is provided with a tapered socket I3 within which the inner or rear end of a shank I2 is adaptedto befirmly secured.

In. order toprovide a means whereby a tool which is ,operatively connected with the spindle II will form a tapered bore, I have provided it cage or frame structure, generallydesignated as I4, which is adapted to be secureclby fastening members-l5a to the faceplate I 0. The cage or frame l lcomprisesa rear annular plate I5, a forward annular plate 161, and an opposed pair of connectingobars l1, .The connecting bar l1 may be cast. with or welded to the plates 15 and l 6 so that tl ieiforward plate l6 will be ri idly supported -in ,a ,position coaxial with the. face plate Ill; The oa eflialso' includes a pair .of spaced apart parallel bars J8 and I9 and asecond pair of spaced apart parallel bars 20 and ZL The pairs of bars [8 and I9 and 20 and 2| laredia metrically disposed. An endwise movable spin dle H is "slidably. mounted thro gh a central opening 23 formed in the plate 15 and shaft 22 is slidable in a central. opening 24 which is formed. in the platejfi'. p I V ,i The shaft '22. hasthe tapered shank 12 extending fromthe' r'ear enfdflthereof and is adapted to' be non-rotatablewith respect to thespindle or socket'meinber Hi The shaft 22 has formed therein a'lengthwise extending slot 25' within which a tool holdingbar or member 26 is rockably mounted. The bar '26 is rockably carried by a pivot boltoi' member 21 extending diametrically through the shaft' 23 at a point between the ends brin shaft and preferably the pivot. memv the shaft 22 as indicated at 30, o as to provide a.

smooth unbroken peripheral surface for the forward end of the shaft 22. The tool holding bar 26 is provided at its forward endwith a head 3| having an opening 32 therein, within which a cutting tool is adapted to be positioned and firmly secured by means of a set-screw 33. As shown in Figure 1, the. face plate H1. is provided with. a diametric key 34 which is adapted? to engage: a keyway 35 formed in the rear or inner side of the rear plate I5. The rear plate l5 may be formed, a. with a plurality of threaded openings 36 for re-" ceiving the securing members I5 2 A cap, enerally designated 2.5.31, isadiustably mounted on the forward plate IK', the latter be" ing formed with peripheral threads 38 and the justing the guide bar supporting plate 42 with reposition the: guide bar supporting plate 42 in the cap 31 bein formed with interiortlireada 39 en- I.

gaging the threads 38. The cap 3'! is provided.

with a central opening 40 through whichthe for- Ward end of the shaft 22 slidably engages.

The cap 3'! also includes an eccentricaliydisposed annular socket or recess 4! within which a disk" or plate 421g loosely mounted; The plate 42- is provided with a relatively large central opening 43 through which the shaft ZZlcoseiy engages; The plate I 2' is provided? in its inner" or rear face with a: pair of recesse'sfl and- 65 within which the forward reduced ends 46 and 41 of a: pair'o'f elongated guide bars 48 and 43 respectively are adapted to rockabiy engage. The guide bar #8 looselyengaees between the cage bars f8 and f3 and has extending through the rear end portion thereof,v a pivot bolt 5U which extends throug'lrth'e edges 52 and 5 are adapted tobe disposed in parallelism at all timesso that the two shoes 53 andiiim'ay freely slide along; these guide surfaces. A. bolt 56" is extended through the rearend portion. of the tool" holding bar 26 being formed with arib' 5'! between the ends thereof engaging one edge. of the tool holdingfbar 26, and v a nut 58 is threaded on the bolt 53 and firmly holds this bolt in. the rear end" of'the tool holding bar 25; A socket member 59. is threaded on one end of the bolt 56 beingprovideci with a concave socket 6G in its outer end' within which the substantially semi-circular inner face of the shoe 53 is adapted to'rockably engage. The" shoe 53 is formed; with a substantially semi-circular rib 6t engaging.in thesocket'member 59' so that the shoe '53 will be held agaihstlaterallmovement with respect to the socket member 59a The shoe is provided with a; substantially semi -circular inner surface and is also formed with at substantially semi-"circularrib '62 which til) engages B; 806K615 63 threaded 0H the end. of: th'ebolt peripheral siniace' or the cap member 3 is.- fomred with graduations 6'4- and a-ealibr'atingplate Eliot segimenta-l' configuration is secured by fastenin asto 'prowtieaveryfinexadiustmg means for ail-- ju'stin'g the eccentric socket Elf and 'tlierebyad' desired. position with respect to the axial center ofthe shaft 21. The exact position .of the eccentric socket 4i and the plate 42 may be deter- Ininedl bythe correlated graduations 64 and 61. After the cap 31 has been rotatably adjusted to the desired position, it may be locked in its adjusted position by means of a, locking plug 68, which i 'sloosely mounted a socket- 69 carried by the cap member 31. A set-screw orpiug looking and releasing member W is threaded into the cap 3*! and bears against the inner end of the plug 58. The rear end of the-plug bears against 7 the forward side oithe forward platel 6. When the cap 31 has been properli adjusted the boring: machine may be operated in the usual manner and at this time the spindle tr will move end-wise withrespect to the cage w. Endw-ise movement of the spindlel f will move the shaft 22 to the left as viewed Figure I and as the shaft 22 moves" outwardly the boring bar- 26 will berockedonpivot 21 as the shoes 53- and tosuce forwardly over the guide surfaces 5 2 and 54-. As the guide surfaces 512- and? are disposed on an angle with respect tra nee-longitudinal axis of the shaft 22, the tool holder iliwvill be rocked sothat the forward cutting end' thereof will form a tapered bore as the shaft 22 moves forwardly on its cutting cycle. 7 This deviceha'sbeen designed asan attachment for a cormen-tionai boring mill or machine and in actual practice hasbeenfound to cut a tapered bore accurately and in a manner to eliminate the subsequent reaming oft'he bore.

What we claim is: 7 V

A taper boring attachmentfor a boring machine having a rotatable face plateanda rotat able and endwise movable spindle; comprising a cage-for attachment to and rotation with said face plate, said cage comprising-a pair of spac'edapart plates; a plurality of'barsi'lxedlyconnecting said plates together, a shaft loosely eng'agin'g' axially through said plates and adapted to be secured to said spindle for rotation and endwise movement therewith, a tool holder rockabiy carried by said shaft and extending lengthwise thereof, a pair of guide bars carried by said cage lengthwise thereof and disposed at anangle to the longitudinal axis of said." shaft, andmeans carried by said toolend-of each bar to said cage member, and means 7 rotatably adfjustablerelati ve to-s ai'd cagemem'ber V supporting theoppositeends of said-bars.

A taper boring attachment as, set forth in H claim 1 including means pivotallyfse'curing one end of each bar to saidv cage-member, and means carried by one ofv said pairof plates and circumferentiaiIy'ad-justable' relativetheretosupporting. 1 1 J p iite"ends-of"saidbars.

4. A boring attachment as set forth in claim 1 including means pivotally securing one end of each bar to said cage member, a circumferentially adjustable cap carried by one of said plates, said cap having an eccentrically disposed recess therein, a, bar adjusting plate loosely engaging in said recess and formed with means rockably supporting the opposite ends of said bars, circumferential adjustment of said cap effecting angular adjustment of said bars.

5. A boring attachment as set forth in claim 1 including means pivotally securing one end of each bar to said cage member, a circumferentially adjustable cap carried by one of said plates, said cap having an eccentrically disposed recess therein, a bar adjusting plate loosely engaging in said recess and formed with means rockably supporting the opposite ends of said bars, circumferentially adjustment of said cap effecting angular adjustment of said bars, and a stop member adjustably carried by said cap for limiting the adjustment thereof in at least one direction.

6. A boring attachment as set forth in claim 1 including means pivotally securing one end of each bar to said cage member, a circumferentially adjustable cap carried by one of said plates, said cap having an eccentrically disposed recess therein, a bar adjusting plate loosely engaging in said recess and formed with means rockably supporting the opposite ends of said bars, circumferential adjustment of said cap effecting angular adjustment of said bars, and correlated graduations carried by said cap and said cage member whereby said cap may be finely adjusted.

7. A taper boring attachment for a boring machine having a rotatable face plate and a rotatable and endwise movable spindle, comprising a cage for attachment to and rotation with said face plate, a shaft loosely engaging through said cage and adapted to be secured to said spindle for rotation and endwise movement therewith, a tool holder rockably carried by said shaft and extending lengthwise thereof, guide bars carried by said cage lengthwise thereof and disposed at an angle to the longitudinal axis of said shaft, means carried by said tool holder engageable with said guide bars whereby to effect rocking of said tool holder simultaneously with the endwise movement of said shaft, and correlated means carried by said guide bars and said cage for selectively varying the angle of said guide bars.

8. A taper boring attachment for a boring machine having a rotatable face plate and a rotatable and endwise movable spindle comprising a cage for attachment to and rotation with said face plate, a shaft loosely engaging through said cage and adapted to be secured to said spindle for rotation and endwise movement therewith, a tool holder rockably carried by said shaft, guide means rockably carried by said cage lengthwise thereof and disposed at an angle to the longitudinal axis of said shaft, means carried by said tool holder engageable with said guide means to effect rocking of said tool holder upon endwise movement of said shaft, and means carried by said cage engageable with said guide means for selectively varying the angle of said guide means.

LOUIS V. MEADOR. ROY J. McDANIEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Oyen Sept. 20, 1932 

